Word Count: ~2,400 words | Reading Time: 10 minutes
The Problem: Everyone Uses These Terms Incorrectly
Walk into any procurement meeting and you'll hear: "We need biodegradable packaging." Dig deeper and what they actually mean varies wildlyβfrom "breaks down eventually" to "customers can compost it at home" to "meets EN 13432 certification."
This confusion isn't academic. It has real consequences:
- Regulatory compliance issues: Claiming "biodegradable" without specification may violate green claims guidelines
- Infrastructure incompatibility: Compostable packaging going to facilities that can't process it
- Customer frustration: Home compostable claims on industrially-compostable-only products
- Wasted R&D investment: Developing products for the wrong end-of-life pathway
As a paper converter working with food businesses for 50+ years, we've seen this confusion cost companies tens of thousands in reformulation, regulatory challenges, and damaged brand reputation.
This article provides the technical clarity you need to make informed decisions.
Key Insight
All compostable materials are biodegradable, but not all biodegradable materials are compostable. The difference matters legally, operationally, and environmentally.
Section 1: Defining the Terms Properly
Biodegradability: The Broad Concept
Scientific Definition: The capability of a material to be broken down by living organisms (primarily bacteria and fungi) into natural substances like water, carbon dioxide, and biomass.
The Critical Variables:
- Timeframe: "Eventually" is meaningless. Standards require specific timeframes (typically 6-12 months)
- Conditions: Temperature, moisture, oxygen, microbial population all affect degradation rate
- Completeness: Partial breakdown leaving microplastics or residues doesn't count
- Environment: Landfill conditions differ drastically from soil, marine, or industrial composting
Relevant Standards:
- ISO 14855: Biodegradability under controlled composting conditions
- ASTM D5988: Soil biodegradation
- ISO 14851: Aquatic environment biodegradability
- EN 13432: Specific requirements for packaging recoverable through composting
Compostability: The Specific Subset
Scientific Definition: The ability to break down in a composting environment (industrial or home) within a specific timeframe, without leaving toxic residues, while supporting plant growth.
EN 13432 Requirements (European/UK Standard):
To claim "compostable," packaging must meet ALL four criteria:
- Disintegration: After 12 weeks in industrial composting, <10% of material remains on a 2mm sieve
- Biodegradation: At least 90% of organic material converts to CO2 within 6 months
- Ecotoxicity: Resulting compost supports plant growth without toxic effects
- Heavy metals: Content below specified thresholds (no contamination)
Critical Distinction - Industrial vs. Home Composting:
- Industrial composting: 58-70Β°C, controlled moisture, active turning, 12-16 weeks
- Home composting: 20-40Β°C, variable moisture, occasional turning, 6+ months
Materials certified for industrial composting may NOT break down in home composting conditions. This distinction causes massive consumer confusion.
Certification Bodies:
- TΓV Austria (OK compost, OK compost HOME)
- DIN CERTCO
- BPI (US, but recognized in UK)
- Seedling logo (European Bioplastics)
Warning
'Compostable' without specification of industrial or home conditions is effectively meaningless and may violate CMA green claims guidance.
Section 2: How Paper Packaging Actually Degrades
Uncoated Paper: The Baseline
Pure cellulose fiber (uncoated, unprinted paper) is naturally biodegradable and compostable:
- Timeframe: 2-4 weeks in industrial composting, 6-12 weeks in home composting
- Conditions: Requires moisture and aerobic conditions
- Residues: Noneβcomplete conversion to CO2, water, and biomass
- Standards: Easily meets EN 13432 and home compost standards
The Catch: Uncoated paper has limited functional properties. Most food applications require moisture resistance, grease barriers, or release propertiesβwhich means coatings.
The Coating Problem
Every functional coating affects biodegradability. Here's the honest assessment:
Wax Coatings (Paraffin and PE Wax)
Composition:
- Paraffin wax: Petroleum-derived long-chain hydrocarbons
- PE wax: Low molecular weight polyethylene
Biodegradability:
- Timeframe: Paraffin: partial degradation over 12-24 months under ideal conditions; PE wax: minimal degradation over years
- Standards compliance: Neither meets EN 13432 requirements
- Environmental fate: Persistent in environment, does not support composting
Why We Still Use It: Excellent moisture barrier, food-safe, cost-effective, recyclable in many UK paper mills
Bio-Wax Alternatives (Soy, Beeswax, Plant-Based)
Composition: Triglycerides and fatty acids from renewable sources
Biodegradability:
- Timeframe: 8-16 weeks in industrial composting
- Standards compliance: Can achieve EN 13432 with proper formulation
- Environmental fate: Complete biodegradation to CO2 and water
Trade-offs:
- 25-40% cost premium over petroleum wax
- Lower melting point (stability issues in warm conditions)
- Variable performance with different paper substrates
- Still requires testing for each specific application
Real-World Example: We developed a bio-wax-coated butcher paper for a regional food retailer. EN 13432 testing confirmed industrial compostability, but the product failed in summer months due to wax softening. Solution required reformulation with higher-melting-point bio-wax blend, adding 15% to cost.
Honest Assessment
Bio-waxes are not drop-in replacements. Every application requires specific formulation and testing. Budget accordingly.
Silicone Release Coatings
Composition: Polydimethylsiloxane (PDMS) polymers
Biodegradability:
- Timeframe: Effectively non-biodegradable in relevant timeframes
- Standards compliance: Does NOT meet EN 13432
- Environmental fate: Persistent, chemically stable
Why We Use It: Essential for release applications (interleaving, baking papers) where no alternative matches performance
Disposal Strategy: Silicone-coated papers should target recycling, not composting
Aqueous/Dispersion Coatings
Composition: Water-based polymer dispersions (typically acrylic, styrene-acrylic, or modified starch)
Biodegradability:
- Timeframe: Highly variableβstarch-based: 4-8 weeks; synthetic polymers: 6-24 months or more
- Standards compliance: Starch-based can meet EN 13432; synthetics typically don't
- Environmental fate: Depends entirely on polymer chemistry
Performance Limitations: Lower moisture and grease resistance than wax or silicone
Section 3: The Printing Ink Complication
Food-Safe Doesn't Mean Compostable
Most food-contact paper packaging is printed. Inks add another layer of complexity:
Water-Based Flexographic Inks (Our Standard):
- Components: Pigments, resins, water, additives
- Biodegradability: Pigments are typically not biodegradable; resins vary
- EN 13432 Impact: Can prevent certification if coverage is high or pigments contain heavy metals
- Best Practice: <5% surface coverage for compostability; use mineral pigments
UV-Curable Inks:
- Not suitable for compostable packaging
- Used only on non-food-contact surfaces where compostability isn't required
Reality Check
Full-color printed packaging rarely achieves EN 13432 certification. If compostability is critical, design with minimal printing or use certified ink systems (at premium cost).
Section 4: Testing and Certification Process
What EN 13432 Testing Actually Involves
Achieving certified compostability isn't simple or cheap:
Testing Requirements:
- Disintegration Test (12 weeks)
- Cost: Β£2,000-3,500
- Process: Industrial composting simulation with active monitoring
- Pass criteria: <10% residue on 2mm sieve
- Biodegradation Test (6 months)
- Cost: Β£3,000-5,000
- Process: CO2 evolution measurement in controlled bioreactors
- Pass criteria: β₯90% conversion to CO2
- Ecotoxicity Test
- Cost: Β£1,500-2,500
- Process: Plant growth trials with compost containing test material
- Pass criteria: β₯90% germination and biomass vs. control
- Heavy Metals Analysis
- Cost: Β£500-1,000
- Process: Chemical analysis of material
- Pass criteria: Levels below EN 13432 limits
Total Cost for Full EN 13432 Certification: Β£7,000-12,000 per product configuration
Timeline: 9-12 months from submission to certification
Important: Certification is product-specific. Changing coating thickness, paper substrate, or printing coverage requires re-testing.
Section 5: UK Composting Infrastructure Reality
The Harsh Truth About Industrial Composting
UK Industrial Composting Capacity (2024):
- Approximately 250 industrial composting facilities
- Total capacity: ~3 million tonnes annually
- Primarily designed for food and garden waste
The Packaging Problem: Most facilities don't want certified compostable packaging:
- Contamination Risk: Difficult to distinguish from non-compostable packaging
- Processing Time: Packaging takes longer to break down than food waste
- Quality Standards: Packaging residues affect compost quality certification
- Economic Model: Food waste processing is profitable; packaging processing isn't
[QUOTE: Industry Expert - "We're certified to accept EN 13432 packaging, but we actively discourage it. Sorting complexity and extended processing time make it economically unviable." - Composting Facility Manager, Midlands]
Collection System Gap:
- Most UK councils don't separate compostable packaging from food waste
- No clear consumer guidance on disposal
- Risk of contaminating recycling streams
Home Composting: Even More Complicated
Home Composting Reality:
- 4-5 million UK households have compost bins/heaps
- Average temperature: 20-40Β°C (vs. 58-70Β°C industrial)
- Variable moisture, irregular turning
- Timeframe: 6-24 months
Product Performance: Materials certified "OK compost HOME" (higher standard than EN 13432) may still take 12+ months to fully degrade in typical UK home composting conditions.
Brutal Honesty
If your business model depends on consumers successfully home composting your packaging, you're building on questionable foundations. UK consumer education and infrastructure aren't there yet.
Section 6: Decision Framework for Food Businesses
When Biodegradable/Compostable Makes Sense
Strong Use Cases:
- Event Catering and Food Service
- Controlled disposal environment
- Can contract with commercial composters
- Volume justifies collection logistics
- Examples: Festival serviceware, stadium food packaging
- Agricultural Applications
- Direct soil incorporation possible
- Outdoor degradation acceptable
- Examples: Seed tapes, plant protection wraps
- Niche Markets with Education Budget
- Premium positioning
- Customer base values sustainability
- Willing to invest in consumer education
- Examples: High-end delis, organic food brands
Poor Use Cases:
- Mass-Market Retail
- Consumer confusion about disposal
- No collection infrastructure
- Cost premium difficult to justify
- Risk of contaminating recycling streams
- Applications Requiring Extended Shelf Life
- Compostable materials can degrade during storage
- Moisture sensitivity issues
- Examples: Long-shelf-life dried goods
- When Recycling Is Available
- Paper recycling is mature, effective, and economically viable
- Why chase compostability when recycling works?
Section 7: Alternatives to Consider
Recyclable Paper: The Pragmatic Default
For most food applications, optimizing for recyclability delivers better environmental outcomes than compostability:
Advantages:
- Established UK infrastructure (75% paper recycling rate)
- Economic value keeps materials in system
- Multiple recycling cycles possible
- Lower cost than compostable alternatives
Design Principles:
- Minimize coating coverage
- Use recyclability-compatible coatings (avoid silicone where possible)
- Water-based inks only
- No mixed materials (paper + plastic laminations)
Home-Washable and Reusable
For specific applications, washable paper (actually cellulose-based reusable material) offers interesting properties:
- Durability through 40-60 washing cycles
- Biodegradable after service life
- Premium positioning
- Examples: Reusable food wraps, storage solutions
Section 8: Regulatory and Claims Guidance
UK Green Claims Code
The CMA (Competition and Markets Authority) provides clear guidance on environmental claims:
To claim "biodegradable":
- Must specify timeframe and conditions
- Must have robust evidence
- Cannot imply rapid or complete degradation without proof
To claim "compostable":
- Must specify industrial or home composting
- Must state certification standard (EN 13432 or equivalent)
- Must be accurate about disposal infrastructure availability
Legal Reality
Claiming 'biodegradable' without meeting ISO 14855 or similar standard, or 'compostable' without EN 13432 certification, exposes your business to regulatory action and reputational damage.
Example of Compliant Claims: β "Industrially compostable to EN 13432 standard. Not suitable for home composting." β "Biodegradable in industrial composting conditions within 12 weeks."
Examples of Non-Compliant Claims: β "Eco-friendly biodegradable packaging" β "Compostable" (without specifying industrial or home) β "Breaks down naturally"
Conclusion: Making the Right Choice
After decades of working with food businesses on packaging sustainability, our advice is:
1. Start with the End in Mind What disposal infrastructure is actually available to your customers? Design for that reality, not an ideal future.
2. Recyclability First for Most Applications Unless you have specific reason to pursue compostability (controlled disposal, regulatory requirement, strong market positioning), optimize for recyclability.
3. If Pursuing Compostability:
- Budget Β£10,000-15,000 for testing and certification
- Specify industrial vs. home clearly
- Have honest conversation with customers about disposal
- Don't assume infrastructure exists
4. Be Honest in Your Claims Vague green claims harm your brand and the industry. Specificity and evidence protect you.
5. Partner with Knowledgeable Converters Not all paper converters understand the nuances. Ask about testing experience, coating options, and infrastructure knowledge.
[CTA: "Need to evaluate biodegradable or compostable options for your food packaging? Our technical team provides free initial consultation including infrastructure assessment and cost-benefit analysis. Contact us to discuss your specific requirements."]
Related Articles
- [Main Article: Sustainable Paper Packaging - Full Lifecycle Guide]
- The Hidden Carbon Footprint: Manufacturing, Transport, and the UK Advantage
- Wax Coatings and Release Agents: Balancing Performance with Environment
- Beyond Recycling: Designing for Circular Economy Compliance
Technical Resources:
- EN 13432 Standard (Full Text): [URL]
- CMA Green Claims Code: [URL]
- UK Composting Facility Locator: [URL]